sourcemaps.io incorrectly throws a SourceMapNotFoundError on my CSS

[rhaglennydd]

Environment

How do you use Sentry?
Sentry SaaS (sentry.io) or self-hosted/on-premise (which version?)

Which SDK and version?
e.g: JavaScript 5.11.1, .NET 1.2.0

Steps to Reproduce

1. Go to https://sourcemaps.io/.
2. Enter http://www.ternaviationgroup.dreamhosters.com/wp-content/themes/tern-aviation-group/dist/css/app.css as the URL.
3. Click Validate.

Expected Result

Anything but a SourceMapNotFoundError.

Actual Result

It says "SourceMapNotFoundError: Unable to locate a source map in http://www.ternaviationgroup.dreamhosters.com/wp-content/themes/tern-aviation-group/dist/css/app.css". Under Resolutions it includes "Add a//# sourceMappingURL= declaration". If you look at the CSS source it has a sourceMappingURL= declaration at the end: /*# sourceMappingURL=app.css.map */. The URL http://www.ternaviationgroup.dreamhosters.com/wp-content/themes/tern-aviation-group/dist/css/app.css.map is valid. Does it need to be an absolute path?